Sunday, November 30, 2008

Sunday November 30, 2008
Embolization of Cerebral Aneurysm

Saturday, November 29, 2008

Saturday November 29, 2008
Glutamine (GlutaSolve)

Emerging literature in Critical Care nutrition shows that Glutamine supplement improves survival from Multi Organ Failure. Low plasma glutamine has been shown to be an independent predictive factor for a poor outcome. Glutamine is linked to improved immune function and fewer infections.

Glutamine is a dietary non-essential amino acid, however during situations of extreme stress a deficiency develops. Ideally, it needs 20-40 gram glutamine per day to restore plasma glutamine levels to normal.

A major demand for glutamine via glutamate is for the production of the major cellular anti-oxidant glutathione. Low intramuscular glutathione levels are correlated with low glutamine and glutamate levels in the critically ill patients. Glutamine has been shown protective to intestinal cells. Patients with severe burns, who were nevertheless fed enterally, showed a significant reduction in septicemia.

Delivery of 30g/day of glutamine jejunally in multiple-trauma patients led to a significant reduction in pneumonia, bacteraemia, and severe sepsis.

Practically, Glutamine (
GlutaSolve) can be given via enteral route 1 packet (15 gram) twice a day after mixing in 100 cc of water.

Contraindications are acute renal failure without dialysis and moderate to severe hepatic failure.

Reference: Click to get article

Glutamine in the critically ill , Richard D Griffiths, Professor of Medicine (Intensive Care), University of Liverpool, UK. , lecture in Paris, June 9-10, 2005 - pdf file

Thursday, November 27, 2008

Thursday November 27, 2008

Q: Why IV Amiodarone cause hypotension?

A: Hypotension from IV amiodarone (particularly bolus) is not due to amiodarone itself but due to its solubilized vehicle called polysorbate 80.

Polysorbate 80 itself can decreases heart rate by depressing AV nodal conduction and has property of increasing atrial and ventricular myocardial refractory period but can cause hypotension due to histamine releasing effect.Polysorbate 80 is also blamed for Acute amiodarone-induced hepatitis but literature is scant on it.

References: click to get abstract/article

1. Pharmacology and Toxicology of a New Aqueous Formulation of Intravenous Amiodarone (Amio-Aqueous) Compared with Cordarone IV. - American Journal of Therapeutics. 12(1):9-16, January/February 2005.

2. Effects of amiodarone with and without polysorbate 80 on myocardial oxygen consumption and coronary blood flow during treadmill exercise in the dog - J Cardiovasc Pharmacol. 1991 Jul;18(1):11-6.

3. Histamine-releasing properties of Polysorbate 80 in vitro and in vivo: correlation with its hypotensive action in the dog - Agents Actions, 1985 Sep;16(6):470-7.

4. I.V. Amiodarone: What Do We Really Know About It? Cardiac Electrophysiology Review, Volume 2, Number 1 / March, 1998

5. Early acute hepatitis with parenteral amiodarone: a toxic effect of the vehicle? - Gut, Vol 34, 565-566, 1993

Wednesday, November 26, 2008

Wednesday November 26, 2008
Bedside trick

In scenarios where patient remains sleepy and delays extubation, it may be of help to try Ritalin 10 mg every 8 hours.

Ritalin (methylphenidate), is a mild central nervous system stimulant and helps in stimulating patient from prolong sedation

Tuesday, November 25, 2008

Tuesday November 25, 2008
Acute kidney injury in ICU patients: a comparison between the RIFLE and the Acute Kidney Injury Network classifications

AKIN=Acute Kidney Injury Network (AKIN) criteria
RIFLE=Risk, Injury, Failure, Loss of Kidney Function, End-stage Kidney Disease criteria

This study evaluated the incidence of acute kidney injury and compared the ability of the maximum RIFLE and of the maximum AKIN within intensive care unit hospitalization in predicting inhospital mortality of critically ill patients.

Methods: Patients were retrospectively evaluated. Chronic kidney disease patients undergoing dialysis or renal transplant patients were excluded from the analysis.

Results: In total, 662 patients (mean age, 58.6 ± 19.2 years; 392 males) were evaluated.
  • AKIN criteria allowed the identification of more patients as having acute kidney injury (50.4% versus 43.8%,) and classified more patients with Stage 1 (risk in RIFLE) (21.1% versus 14.7%), but no differences were observed for Stage 2 (injury in RIFLE) (10.1% versus 11%) and for Stage 3 (failure in RIFLE) (19.2% versus 18.1%).
  • Mortality was significantly higher for acute kidney injury defined by any of the RIFLE criteria (41.3% versus 11%) or of the AKIN criteria (39.8% versus 8.5%).
  • There were no statistical differences in mortality by the acute kidney injury definition/classification criteria.

Conclusions: Although AKIN criteria could improve the sensitivity of the acute kidney injury diagnosis, it does not seem to improve on the ability of the RIFLE criteria in predicting inhospital mortality of critically ill patients.

Above pearl is contributed by:

Tony Halat, MD - Clinical Instructor in Medicine, Department of Medicine, The Methodist Hospital, Weill Medical College, Cornell University

Reference: Click to get article

Acute kidney injury in intensive care unit patients: a comparison between the RIFLE and the Acute Kidney Injury Network classifications- Critical Care 2008, 12:R110

Monday, November 24, 2008

Monday November 24, 2008
RIFLE Criteria for Acute Renal Dysfunction

Increased creatinine x 1.5 or GFR decrease more than 25%
UO less than 0.5ml/kg/h x 6 hr

Increased creatinine x2 or GFR decrease more than 50%
UO less than 0.5ml/kg/h x 12 hr

Increase creatinine x3 or GFR decrease more than 75%
UO less than 0.3ml/kg/h x 24 hr or Anuria x 12 hrs

Persistent ARF = complete loss of kidney function more than 4 weeks

End Stage Kidney Disease (> 3 months)

GFR; Glomerular Filtration Rate
ARF; Acute Renal Failure
ESKD; End Stage Kidney Disease

Above pearl is contributed by:

Tony Halat, MD, Clinical Instructor in Medicine, Department of Medicine, The Methodist Hospital Weill Medical College, Cornell University

Sunday, November 23, 2008

Sunday November 23, 2008


Saturday, November 22, 2008

Saturday November 22, 2008

Why Etomidate may not be a good choice in neurological and neuro-surgical patients ?

A: It may decrease the seizure threshold.

Etomidate has fall out of favor in medical ICUs for intubation due to its transient effect of causing adrenal insufficiency, which makes it undesirable in septic patients. But another less known side effect is its ability to decrease the threshold for seizure.Despite its effect on above 2 groups of patients, it is still a very valuable drug to use during intubation (atleast in other patients) due to its quality of having minimal effect on hemodynamic changes, faster effect (15 sec) and quick recovery (3-7 mins). Adrenocortical suppression after single dose is transient which last for 12-36 hours.

See nice review article: Should We Use Etomidate as an Induction Agent for Endotracheal Intubation in Patients WithSeptic Shock? - A Critical Appraisal from Dr. William L. Jackson, Critical Care Medicine Service, Department of Surgery, Walter Reed Army Medical Center, Washington, DC. (Chest. 2005;127:1031-1038.)

Friday, November 21, 2008

Friday November 21, 2008

Is there a difference in metabolism between Cleviprex (clevidipine butyrate) and other dihydropyridine Calcium Channel blocker?

IV Clevidipine butyrate(
cleviprex) is rapidly metabolized by hydrolysis of the ester linkage, primarily by esterases in the blood and extravascular tissues. In contrast, earlier generation of dihydropyridine calcium channel blockers, such as nicardipine or nifedipine are metabolized by liver or kidney. It can be titrated depending on the response of the individual patient to achieve the desired blood pressure reduction.

The elimination of clevidipine butyrate is unlikely to be affected by hepatic or renal dysfunction. Therefore, no dosing adjustment is necessary in patients with renal or hepatic dysfunction. Unlike nicardipine, the clevidipine does not accumulate in the body, and its clearance is therefore independent of body weight.

Thursday, November 20, 2008

Thursday November 20, 2008
Citrate in CRRT

Q; Why we use citrate (when heparin is not used) to avoid filter clotting inCRRT / CVVHD (continuous renal replacement therapy) ?

A: Citrate combines with calcium and cause extracorporeal chelation of calcium and blocks calcium dependent steps of clotting cascade.When extracorporeal blood mix with venous blood, the ionized calcium level get resotred and systemic anticoagulation get avoided. Also citrate get metabolized via liver and chelated calcium get release back in circulation which prevents hypocalcemia (though frequent checks required particularly in liver insuff.).

Related: Very nice review article: Acute Renal Failure in ICU

(reference:, december 2006, volume 4, issue 10) - pdf file

Wednesday, November 19, 2008

Wednesday November 19, 2008
Probiotics for oral decontamination

Chlorhexidine (CHX) is commonly used to decontaminate the oral cavity to prevent ventilator associated Pneumonia (VAP). CHX has several side effects including discoloration of teeth, burning taste, local irritation. Bacteria can develop resistance to CHX specially MRSA.

Recently Klarin et all studied the role of Probiotic bacteria Lactobacillus plantarum 299 (Lp299) and found to be equally effective to prevent colonization of pathogens in mechanically ventilated patients

Related previous pearl:
C-difficile and probiotic drink

Reference: Click to get abstract

Use of the probiotic Lactobacillus plantarum 299 to reduce pathogenic bacteria in the oropharynx of intubated patients: a randomised controlled open pilot study - Critical Care 2008, 12:R136

Tuesday, November 18, 2008

Tuesday November 18, 2008

Characteristics of IV Antihypertensive agents

The following medicines are described for five effects

  1. Therapy class
  2. Onset of Action
  3. Duration of action
  4. Preload
  5. Afterload

Nicardipine is Dihydropyridine Calcium Channel Blocker with onset in 5-10 minute and duration of action 2-4 hours. It has No effect on Preload but decrease afterload.

Clevipidine Nicardipine is Dihydropyridine Calcium Channel Blocker with onset in 1 minute and duration of action 10 minutes. It has No effect on Preload but decrease afterload.

Esmolol is Dihydropyridine Beta Blocker with onset in 6-10 minutes and dutation of action 20 minutes. It has No effect on Preload or afterload.

Fenoldopam is Dihydropyridine Dopamine-D1 like receptor agonist with onset in 10-15 minutes and duration of action 10-15 minutes. It has No effect on Preload but decrease afterload.

Hydralazine is Arterial Vasodilator with onset in 10 minutes and duration of action 2-6 hours. It has No effect on Preload but decrease afterload.

Labetolol is Selective alpha and non-selective beta adrenergic receptor blocker with onset in 5-10 minutes and duration of action 2-6 hours. It has No effect on Preload but decrease afterload.

Nitroglycerine is Nitrovasodilator with onset in 2-5 minutes and duration of action 10-20 minutes. It has No effect on Preload and minimal effect on afterload.

Sodium nitroprusside is Nitrovasodilator with onset in few seconds and duration of action 1-2 minutes. It has decrease Preload and afterload.

Monday, November 17, 2008

Monday November 17, 2008
Low tidal volume and PEEP as per ARDS NET trial not good enough?

Study by Daniel Talmor recently published in NEJM addresses this issue. They used esophageal pressure monitoring to guide the changes made on mechanical ventilation.

Method: They randomly assigned patients with acute lung injury or ARDS to undergo mechanical ventilation with PEEP adjusted according to measurements of esophageal pressure (the esophageal-pressure–guided group) or according to the Acute Respiratory Distress Syndrome Network standard-of-care recommendations (the control group).

The primary end point was improvement in oxygenation. The secondary end points included respiratory-system compliance and patient outcomes.

Results: The study was stopped early as it met its termination criteria after enrolling 61 patients. The ratio of the partial pressure of arterial oxygen to the fraction of inspired oxygen at 72 hours was 88 mm Hg higher in the esophageal-pressure–guided group than in the control group (95% confidence interval, 78.1 to 98.3; P=0.002). This effect was persistent over the entire follow-up time (at 24, 48, and 72 hours; P=0.001 by repeated-measures analysis of variance).

Respiratory system compliance was also better (p-0.01)

Conclusion: As compared with the standard therapy in ARDS, the management of mechanical ventilation by using esophageal pressure to estimate the transpulmonary pressure significantly improves oxygenation and compliance.

Editorial Comment: Agree with author’s conclusion that further study is needed before it is recommended as guideline.

Reference: Click to get abstract/article

Talmor D, Garge T, Malhotra A, et al.
Mechanical Ventilation Guided by esophageal Pressure in Acute Lung Injury. NEJM 2008; 359: 2095-2014

Sunday, November 16, 2008

Sunday November 16, 2008

Q: Which phase of respiration on CXR is better to detect pneumothorax (like after inserting central venous catheter)
- inspiration or expiration ?

A: Expiration

Inspiration or expiration doesn't effect the volume of air in pleural space and pneumothorax can be detected better in expiration with less air volume in lung parenchyma, visually magnifying the air in pleural area.

Saturday, November 15, 2008

Saturday November 15, 2008
Short note on short acting opioids

Sufentanyl, Fentanyl, Alfentanyl and Remifentanyl have gained popularity as preferred analgesics for critically ill patients. These are not associated with hemodynamic changes and can be given to patient with morphine intolerance or allergies. Fentanyl is about 100 times more potent that morphine. The onset of actions is rapid and duration is short. The usual intermittent doses do not need to be adjusted for renal or hepatic failure, however these drugs are metabolized by liver and continuous infusion and large doses can accumulate specially in patients with liver failure. The metabolites are largely inactive.

Remifentanyl is ultrashort acting opiate. Please see review article

The place for short-acting opioids: special emphasis on remifentanil
- Reference: Critical Care 2008, 12(Suppl 3):S5

Reference: click to get article / abstract

Agents for sedation and analgesia in the intensive care unit - Ann Fr Anesth Reanim. 2008 Jul-Aug;27(7-8):560-6. Epub 2008 Jul 1

Friday, November 14, 2008

Friday November 14, 2008
Platelet transfusion

Q: How long does it take for transfused platelet to show apparent effect?

About one hour.Each unit of platelet transfusion is expected to increase platelet count by 5 - 10,000 / uL, and platelet transfusion is usually given as 6 or 10 units together.

Thursday, November 13, 2008

Thursday November 13, 2008

Case: 68 year old patient admitted with CHF. Now with diuresis patient is stabalized and clinically stable to transfer to floor. Patient last CVP noted was 12. Patient bed is raised to perform portable chest x-ray. With elevation of bed, will CVP (choose one)

1. Fall
2. Rise
3. No change

Will rise

CVP transducer and intravascular volume at "zero" point acts as a balance set of fluids. If transducer goes down below zero point (like with elevation of bed) CVP will rise.

Wednesday, November 12, 2008

Wednesday November 12, 2008
Bedside trick - suspecting tracheal aspiration

One quick method of suspecting tracheal aspiration or atleast ruling out tracheal aspiration is checking glucose concentration by regular bedside glucose meters. A glucose concentration of more than 20 mg/dl of bloodless tracheal aspirate doesn't confirm but atleast enhance the suspicion of tracheal aspiration .Though literature is full of conflicting data for this method but still it is a very quick, effective and easy way of suspecting or ruling out tracheal aspiration.

References: click to get abstracts / articles

1. Clinical implications of the glucose test strip method for early detection of pulmonary aspiration in nasogastric tube- fed patients - Taehan Kanho Hakhoe Chi. 2004 Dec;34(7):1215-23
Comparison of blue dye visualization and glucose oxidase test strip methods for detecting pulmonary aspiration of enteral feedings in intubated adults - Chest, Vol 103, 117-121
3. Glucose content of tracheal aspirates: Implications for the detection of tube feeding aspiration. Crit Care Med 1994; 22:1557-1562
4. Glucose Content of Tracheal Aspirates - Letter to the Editor - Critical Care Medicine: Volume 23(8) August 1995 pp 1451-1452 .

Tuesday, November 11, 2008

Tuesday November 11, 2008
Corticosteroids for the Prevention of Atrial Fibrillation
After Cardiac Surgery

Atrial fibrillation (AF) is the most common arrhythmia to occur after cardiac surgery. An exaggerated inflammatory response has been proposed to be one etiological factor. Study was done to test whether intravenous corticosteroid administration after cardiac surgery prevents AF after cardiac surgery. A double-blind, randomized multicenter trial in 3 university hospitals in Finland of 241 consecutive patients without prior AF or flutter and scheduled to undergo first on-pump coronary artery bypass graft (CABG) surgery, aortic valve replacement, or combined CABG surgery and aortic valve replacement.

Intervention: Patients were randomized to receive either 100-mg hydrocortisone or matching placebo as follows: the first dose in the evening of the operative day, then 1 dose every 8 hours during the next 3 days. In addition, all patients received oral metoprolol (50-150 mg/d) titrated to heart rate.

Main Outcome Measure: Occurrence of AF during the first 84 hours after cardiac surgery.

  • The incidence of postoperative AF was significantly lower in the hydrocortisone group (36/120 [30%]) than in the placebo group (58/121 [48%]
  • Compared with placebo, patients receiving hydrocortisone did not have higher rates of superficial or deep wound infections, or other major complications.

Conclusion: Intravenous hydrocortisone reduced the incidence of AF after cardiac surgery.

Reference: Click to get abstract/article

Corticosteroids for the Prevention of Atrial Fibrillation After Cardiac Surgery JAMA. 2007;297:1562-1567.

Monday, November 10, 2008

Monday November 10, 2008
Do we need 8 or 15 days of antibiotics for Ventilator Associated Pneumonia

Chastre and his colleague look at the difference between 8 or 15 days of antibiotics use. Decreasing the duration of antibiotics can help to decrease the resistance.

DESIGN, SETTING, AND PARTICIPANTS: Prospective, randomized, double-blind (until day 8) clinical trial conducted in 51 French ICUs.

A total of 401 patients diagnosed as having developed VAP by quantitative culture results of bronchoscopic specimens and who had received initial appropriate empirical antimicrobial therapy were enrolled between May 1999 and June 2002.

INTERVENTION: A total of 197 patients were randomly assigned to receive 8 days and 204 to receive 15 days of therapy with an antibiotic regimen selected by the treating physician.

MAIN OUTCOME MEASURES: Primary outcome measures-death from any cause, microbiologically documented pulmonary infection recurrence, and antibiotic-free days-were assessed 28 days after VAP onset and analyzed on an intent-to-treat basis.

: Compared with patients treated for 15 days, those treated for 8 days had

  • neither excess mortality (18.8% vs. 17.2%) nor more recurrent infections (28.9% vs. 26.0%)
  • The number of mechanical ventilation-free days, the number of organ failure-free days, the length of ICU stay, and mortality rates on day 60 for the 2 groups did not differ.
  • Although patients with VAP caused by nonfermenting gram-negative bacilli, including Pseudomonas aeruginosa, did not have more unfavorable outcomes when antimicrobial therapy lasted only 8 days, they did have a higher pulmonary infection-recurrence rate compared with those receiving 15 days of treatment (40.6% vs. 25.4%).

CONCLUSIONS: Among patients who had received appropriate initial empirical therapy, with the possible exception of those developing nonfermenting gram-negative bacillus infections, comparable clinical effectiveness against VAP was obtained with the 8- and 15-day treatment regimens. The 8-day group had less antibiotic use.

Reference: click to get abstract/article

Chastre J, Wolf M, Fago JY et al.
Comparision of 8 vs 15 days of antibiotic therapy for ventilator associated pneumonia in adults. JAMA 2003; 290: 2588-2598.

Sunday, November 9, 2008

Sunday November 9, 2008

(3 part videos - Total time 21.08 minutes)

Saturday, November 8, 2008

Saturday November 8, 2008
Do anti-Pseudomonal agents increase the Pseudomonas aeruginosa colonization?

Jose Martinez published a paper in Intensive Care Medicine to clarify the issues.

Setting: Prospective study in two medical ICU.

Measurements: Surveillance cultures from nares, pharynx, rectum and respiratory secretions. Acquisition of resistance was defined as the isolation, after 48 hrs of ICU stay, of an isolate resistant to a given antibiotics.

Results: Forty-four (13%) patients acquired 52 strains of P. aeruginosa.

Administration of piperacillin-tazobactam for more than/= 3 days and use of amikacin for more than/= 3 days were positively associated with acquisition of P. aeruginosa, whereas use of quinolones and antipseudomonal cephalosporins was protective.

Exposure to quinolones and cephalosporins was not associated with the acquisition of resistance, whereas it was linked with usage of all other agents. Neither quinolones nor cephalosporins were a major determinant on the emergence of resistance to themselves, as resistance to these antibiotics developed at a similar frequency in non-exposed patients.

Conclusions: In critically ill patients, quinolones and antipseudomonal cephalosporins may prevent the acquisition of P. aeruginosa and may have a negligible influence on the acquisition and emergence of resistance.


Martinez J, Delgado E, Marti S, Marco F et al. Influence of antipseudomonal agents on Pseudomonas aeruginosa colonization and acquisition of resistance in critically ill medical patients.
Intensive Care Medicine 2008 Published online October 21st 2008.

Friday, November 7, 2008

Friday November 7, 2008
Factors predicting successful noninvasive ventilation in acute lung injury

Noninvasive ventilation (NIV) has been successfully used to treat various forms of acute respiratory failure. It remains unclear whether NIV has potential as an effective therapeutic method in patients with acute lung injury (ALI). The aims of this study were to determine factors predicting the need for endotracheal intubation in ALI patients treated with NIV, and to promote the selection of patients suitable for NIV.

Results: A total of 47 patients with ALI received NIV, and 33 patients (70%) successfully avoided endotracheal intubation.

Patients who required endotracheal intubation had a
  • significantly higher Acute Physiology and Chronic Health Evaluation (APACHE) II score
  • a significantly higher Simplified Acute Physiology Score (SAPS) II
  • a significantly lower arterial pH

The respiratory rate decreased significantly within 1 h of starting NIV only in patients successfully treated with NIV.

An APACHE II score of more than 17 (P = 0.022) and a respiratory rate of more than 25 breaths/min after 1 h of NIV (P = 0.024) were independent factors associated with the need for endotracheal intubation.

Patients who avoided endotracheal intubation had a significantly lower ICU mortality rate and in-hospital mortality rate than patients who required endotracheal intubation.

Conclusion: We determined an APACHE II score of more than 17 and a respiratory rate of more than 25 breaths/min after 1 h of NIV as factors predicting the need for endotracheal intubation in ALI patients treated with NIV.

Above pearl is contributed by:

Tony Halat, MD

Clinical Instructor in Medicine
Department of Medicine,
The Methodist Hospital
Weill Medical College, Cornell University

Reference: click to get article

Factors predicting successful noninvasive ventilation in acute lung injury - Journal of Anesthesia, Volume 22, Number 3 / August, 2008, 201-206

Thursday, November 6, 2008

Thursday November 6, 2008
Index to Predict death in COPD Patients

The BODE index, a simple multidimensional grading system, is better than the FEV1 at predicting the risk of death from any cause and from respiratory causes among patients with COPD.

BODE index is a 10-point scale - higher scores indicate a higher risk of death.
B = The body-mass index (B),
O = The degree of airflow obstruction
D = Dyspnea (D), and
E = Exercise capacity (E), measured by the six-minute–walk test.

Reference: click to get article

Celli BR, Cote CG, Marin JM, Casanova C, et al.
The body mass index, airflow obstruction, dyspnea, and exercise capacity index in COPD. NEJM 2004, 350: 1005-1012..

Wednesday, November 5, 2008

Wednesday November 5, 2008
Does Transfusion increases length of stay

Joseph Datsha and their colleague published a retrospective study on management of anemia in critically ill patients and their effects in American Journal of Therapeutics.

Study was designed to measure
  • to measure packed red blood cell (pRBC) use across different critical care settings;
  • to characterize transfused and nontransfused critically ill patients; and
  • to identify potential predictors of transfusion use.
A retrospective analysis of critically ill patients from 139 hospitals across the United States was conducted.

Results: A total of 180,221 patients met all inclusion criteria, with 29,331 (16.3%) receiving pRBCs during their ICU stay.There was differential use of pRBCs by ICU/coronary care unit setting (i.e., 23% of general ICU patients versus 7% of intermediate coronary care unit patients).

Increasing age, Declining hemoglobin concentrations, Mechanical ventilation, dialysis, Presence of acute renal failure, Congestive heart failure and Septicemia were associated with a higher likelihood of pRBC use.

Each pRBC transfusion significantly increased hospital length of stay (1.6, 0.5, and 2.7 additional days for patients with 1, 2, and 3 or more transfusions, respectively, P <>

Conclusions: Multiple factors increased the likelihood of pRBC use in ICU patients. In addition, pRBC transfusion was associated with increased length of stay.

Reference: click to get article

Dasta J, Modt S, McLaughlin T, LeBlanc J et al. Current Management of Anemia in Critically Ill Patients: Analysis of a Database of 139 Hospitals. Journal of Therapeutics. 2008 15(5):423-430.

Tuesday, November 4, 2008

Tuesday November 4, 2008
Predictors of hospital mortality in a population-based cohort of patients with acute lung injury

Following Pearl is contributed from:

Tony Halat, MD
Clinical Instructor in Medicine
Department of Medicine, The Methodist Hospital
Weill Medical College, Cornell University

Objective: We sought to determine the predictors of mortality in a population-based cohort of patients with acute lung injury and to characterize the performance of current severity of illness scores in this population.

Patients: The cohort included 1,113 patients with acute lung injury identified during the year 1999-2000.

Results: We evaluated physiology, comorbidities, risk factors for acute lung injury, and other variables for their association with death at hospital discharge. Bivariate predictors of death were entered into a multiple logistic regression model. We compared Acute Physiology and Chronic Health Evaluation (APACHE) II, APACHE III, and Simplified Acute Physiology Score II to the multivariable model using area under the receiver operating characteristic curve. The model was validated in an independent cohort of 886 patients with acute lung injury. Modified acute physiology score, age, comorbidities, arterial pH, minute ventilation, Paco2, Pao2/Fio2 ratio, intensive care unit admission source, and intensive care unit days before onset of acute lung injury were independently predictive of in-hospital death. The area under the receiver operating characteristic curve for the multivariable model was superior to that of APACHE III but was no different after external validation.

The predictors of mortality in patients with acute lung injury are similar to those predictive of mortality in the general intensive care unit population, indicating disease heterogeneity within this cohort. Accordingly, APACHE III predicts mortality in acute lung injury as well as a model using variables selected specifically for patients with acute lung injury.

Reference: click to get article

Predictors of hospital mortality in a population-based cohort of patients with acute lung injury - Critical Care Medicine. 36(5):1412-1420, May 2008

Monday, November 3, 2008

Monday November 3, 2008
Impact of Transfusion in Intensive Care Unit

Paul Marik in the article published in Critical care Medicine assessed the independent effect of RBC transfusion on patient outcomes. From 571 articles screened, 45 met inclusion criteria and were included for data extraction.

Study Design: Retrospective study reviews and metaanalysis.

Forty-five studies including 272,596 patients were identified. The overall risks vs. benefits of RBC transfusion on patient outcome in each study were classified as (i) risks outweigh benefits, (ii) neutral risk, and (iii) benefits outweigh risks.


  • In 42 of the 45 studies the risks of RBC transfusion outweighed the benefits.
  • The risk was neutral in two studies with the benefits outweighing the risks in a subgroup of a single study (elderly patients with an acute myocardial infarction and a hematocrit <30%).>
  • Seventeen of 18 studies demonstrated that RBC transfusions were an independent predictor of death. The pooled odds ratio (12 studies) was 1.7 (95% confidence interval, 1.4-1.9).
  • Twenty-two studies examined the association between RBC transfusion and nosocomial infection; in all these studies blood transfusion was an independent risk factor for infection. The pooled odds ratio (nine studies) for developing an infectious complication was 1.8 (95% confidence interval, 1.5-2.2).
  • RBC transfusions similarly increased the risk of developing multi-organ dysfunction syndrome (three studies) and ARDS (six studies). The pooled odds ratio for developing acute respiratory distress syndrome was 2.5 (95% confidence interval, 1.6-3.3).

Conclusions: Despite the inherent limitations in the analysis of cohort studies, our analysis suggests that in adult, intensive care unit, trauma, and surgical patients, RBC transfusions are associated with increased morbidity and mortality and therefore, current transfusion practices may require reevaluation. The risks and benefits of RBC transfusion should be assessed in every patient before transfusion.

Reference: click to get article

Marik P, Corwin HL. Efficacy of red blood cell transfusion in the critically ill: A systematic review of the literature. Critical Care Medicine 2008, 36(9): 2667-2674

Sunday, November 2, 2008

Sunday November 2, 2008
Hemodynamic Classification of Atrial Septal Defects

Saturday, November 1, 2008

Saturday November 1, 2008

Q; What is your diagnosis?

Answer: Atrial fibrillation and complete heart block

In first glance, its hard to miss Atrial fibrillation in above EKG but distinguishing points are

  • Fibrillary waves of atrial fibrillation on close look
  • No P waves.
  • Regular ventricular rhythm

AF with complete heart block is an indication for a permanent pacemaker.